Many prior art documents provide arrangements where a trocar (or other wall penetrating device) is held in place by an abutment on the exterior and an inflated balloon on the interior.
U.S. Pat. No. 3,253,594 issued 1966 to Matthews shows a crude arrangement of this type (called a peritoneal cannula) with a flat washer on the exterior forming an abutment which is held in place by a screw and an inflatable balloon on the interior. The balloon is inflated by a supply of saline from an external source through a lumen which is a simple tube which may or may not be circular in cross-section.
U.S. Pat. No. 4,861,334 issued 1989 to Nawaz shows a more effectively engineered of this type, called a gastrostomy tube, with a domed washer on the exterior held in place by a screw and an inflatable balloon on the interior. The balloon is inflated through a channel in the interior of the tube fed through an exterior port by a supply of air from an external source.
Many subsequent patents are cited as improvements to the arrangement of Nawaz.
In a number of published applications Applied Medical Resources (Albrecht et al) disclose that it is known to attach an inflatable collar to a trocar. For example:
US 2007/0239108 and US 2007/0213675 claim a sleeve as a cannula with a balloon, but are limited to the use of annular grooves and longitudinal channel, to provide the fluid communication from the inlet to the balloon;
US 2009/0221960 claims first and second inflatable sections or balloon and an inlet port. This document mentions that the retention device can be formed as a separate unit for attachment to an existing trocar. This is not a new idea. US 2010/0081994 of Zisow provides a hinged end section of the trocar sleeve which pivots to resist pull out of the trocar.
Telflex Medical and Applied Medical Resources both appear to have related products and an extensive number of previous patents but no additional patents or applications of relevance to this subject have been located.
All publications, patents, and patent applications mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication, patent, or patent application was specifically and individually indicated to be incorporated by reference, or may be referred to for any further details of such devices.